Solve Three Coding Interview Problems
Company: Microsoft
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Technical Screen
The coding round contained three independent problems:
1. **Merge two sorted arrays and remove duplicates.** Given two sorted integer arrays `a` and `b`, return one sorted array that contains each distinct value appearing in either array exactly once.
2. **Find the vertex of a quadratic function within a range.** You can evaluate a quadratic function `f(x)` on integer inputs, and you are given an integer range `[L, R]` that is guaranteed to contain the vertex of the parabola. Find the integer `x` where the function reaches its extremum within that range.
3. **Design and implement a simplified search autocomplete system.** Build a data structure initialized with a collection of strings. It should support inserting a new string and querying a prefix to return all stored strings that begin with that prefix. Unlike a production autocomplete system, you do not need frequency-based ranking or top-`k` truncation.
Quick Answer: This set of problems evaluates competency in algorithmic problem-solving, including merging sorted arrays with duplicate elimination, reasoning about the extremum of a quadratic function within integer bounds, and the design and implementation of prefix-based string search, and falls within the Coding & Algorithms category.